The present invention relates to a ball balancing mechanism for dynamically balancing rotating objects.
Dynamic balancing of rotating objects utilizing balance rings having spherical weights is known in the prior art. However, certain disadvantages are encountered with prior art devices, particularly when the balancing ring is made from plastic. The spherical weights are usually made from metal and during the rotation of the object the spherical weights can deform or damage the plastic as a result of centripetal force.
Therefore, a primary object of the present invention is the provision of an improved ball balancing mechanism for rotating objects.
A further object of the present invention is the provision of an improved ball balancing mechanism having structure that is stiff enough to allow the balls to roll freely even at high centripetal acceleration.
A further object of the present invention is the provision of a rolling surface for the balls which is strong enough to withstand the contact stresses of the rolling balls.
A further object of the present invention is the provision of an improved ball balancing mechanism which is economical to manufacture, efficient in operation, and durable in use.
The foregoing objects may be achieved by a ball balancing mechanism formed from an annular ring having a hollow cross section creating an enclosed hollow annular cavity therein. An annular race is placed within the hollow cavity and extends around the entire circumference of the ring. A plurality of spherical weights are retentively contained with the annular race and are free to roll in a circumferential direction within the annular race around the circumference of the annular ring.
According to one feature of the invention the annular race is comprised of metal and the annular ring is comprised of plastic.
According to another feature of the invention a damping fluid is contained within the hollow cavity and bathes the spherical weights to cause damping of the movement of the spherical weights in the race.
According to another feature of the present invention the race has a C-shaped cross section and the opening of the C-shaped cross section faces generally in an inner radial direction with respect to the annular center of the ring.
The preferred use for the balancing ring is in connection with either a vertical or horizontal axis washing machine tub wherein the annular ring is mounted to the washing machine tub with its central axis aligned with the rotating axis of the washing machine tub.
While the use of the annular ring with a washing machine tub is preferred, the annular ring maybe used for other rotating objects without detracting from the invention.
According to the method of the present invention a balancing ring having a central ring axis is attached to a rotatable object in a position wherein the central ring axis of the balancing ring is aligned with the rotating axis of the object.